A data center of a VXLAN may include a layer 3 gateway device and a layer 2 gateway device. Different layer 3 gateway devices are connected to different layer 2 gateway devices. Different layer 2 gateway devices are connected to different hosts. In this case, one host can directly communicate only with one layer 3 gateway device by using a layer 2 gateway device connected to the host. As a result, a communication manner of the data center is not flexible enough. Herein, that the host directly communicates with the layer 3 gateway device means that communication is performed without using another layer 3 gateway device.
How to enable one host to directly communicate with a plurality of layer 3 gateway devices specifically includes: how to establish a forwarding entry used for communication between the layer 3 gateway devices and the host. This is a problem that urgently needs to be resolved.